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1.
K Aroni AC Lazaris K Papadimitriou H Paraskevakou PS Davaris 《Canadian Metallurgical Quarterly》1998,194(12):855-859
High-level resistance (minimum inhibitory concentration, MIC > 1,000 micrograms/ml) to gentamicin (HLGR) in enterococci is common in Taiwan. In this study, we investigated the distribution of gentamicin resistance elements in enterococci isolated at National Taiwan University Hospital in a 1-year period, and also examined the transfer and the genetic variability of the resistance elements of different isolates. Among 109 isolates tested, 43 (39%) HLGR isolates were identified. HLGR was most common in Enterococcus faecium isolates (7/15, 47%), followed by Enterococcus faecalis (34/80, 43%), Enterococcus avium (1/5, 20%), and Enterococcus casseliflavus (1/9, 11%). To understand the mechanism of resistance transfer, four isolates of E. faecalis and five isolates of E. faecium showing HLGR were studied. Transfer of resistance markers to a plasmid-free recipient strain of E. faecalis JH2-7 was observed, with transfer frequencies ranging from 10(-2) to 10(-8). All of the transconjugants contained plasmids, with sizes ranging from 45 kb to larger than 70 kb. At least three plasmid patterns were observed on digestion with HaeIII. Hybridization with a probe specific for the aac6'aph2" gentamicin resistance gene confirmed that all of these HLGR isolates carried a Gm(r) determinant, though the hybridization patterns of the plasmids from E. faecalis and E. faecium were different. Although many similarities exist among enterococcal Gm(r) determinants, the results suggest heterogeneity may occur in the flanking regions of resistance elements. 相似文献
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P Melgarejo-Moreno D Hellin-Meseguer E Sarroca-Capell 《Canadian Metallurgical Quarterly》1996,34(4):247-248
Merkel cell carcinoma is an aggressive dermal neoplasm of neuroendocrine origin with a predilection for the head-and-neck region in elderly patients. We present a case of Merkel cell carcinoma of the nasal fossa. Local wide excision was performed. 相似文献
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The histologic examination of dental implants retrieved from humans is important to establish the causal determinants of implant failure, and to compare and validate the results obtained from animal studies. This study presents a retrospective review of the histologic features of 230 implants retrieved in an 8-year period (1989-1996). All the implants were treated to obtain thin (20 to 30 microm) ground sections. The majority of implants were retrieved because of mobility (n=56), peri-implantitis (n=54), or fractures (n=90). Peri-implantitis occurred more frequently before (n=44) than after (n=10) abutment connection. A dense fibrous connective tissue with no inflammatory cells was present at the interface in the implants retrieved for mobility; bone was found only in the most apical part. In many of these implants epithelial cells were present. The main histologic features of peri-implantitis consisted of the presence of a bone sequestrum near the implant, many bacteria present on the implant surface, and an inflammatory infiltrate (macrophages, lymphocytes, and plasma-cells) nearby. Histology showed that in the implants removed for fracture, there was a very high percentage (80 to 100%) of peri-implant bone. 相似文献
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A case of congenital oligodendroglioma occurring in a 34th-gestational week fetus is reported. The tumor was necrotic, hemorrhagic, and gelatinous. It covered the basal part of the brain, and almost the entire cerebellum was replaced by the tumor. The tumor cells had small, round, hyperchromatic nuclei and watery clear cytoplasm, and were arranged in a paved or alveolar pattern. Immunohistochemically, S100 protein, myelin-basic protein, neuron-specific enolase and Leu 7 were weakly positive for the cytoplasm, but glial fibrilliary acidic protein, synaptophysin, neurofilament, desmin, and vimentin were negative. Many tumor cell nuclei were positive for mutant p53 protein, and the labeling index was 85%. But there was no genetic alteration in exons 4 to 9 of p53 gene from the peripheral blood. The apoptosis index was 1.5%. Considering the p53 labeling index and the apoptosis index together, this congenital oligodendroglioma may be regarded as potentially malignant despite the benign morphological features. 相似文献
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Carcinoma of the prostate, that is adenocarcinoma, is one of the most common malignancies in the male with an estimated incidence for 1991 of 122,000 new cases. On the other hand, squamous cell carcinoma of the prostate, with a median incidence of .5%-1% of all prostatic malignancies, has a similar clinical presentation but differs in treatment response and prognosis. We herein present one case of this histological pattern and review the literature pertaining to it. 相似文献
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We report herein the extremely unusual case of a 71-year-old woman with signet-ring cell carcinoma of the ileum. She originally presented with a 6-month history of intermittent nausea and abdominal distention, but initial examinations, including gastrointestinal fiberscopy, ultrasonography, and computed tomography (CT) scan, failed to reveal any cause of her symptoms. A barium-enema study performed 11 months after her initial visit demonstrated a narrow portion of the terminal ileum. An ileocecal resection was subsequently performed, and an epigastric subcutaneous tumor was simultaneously excised. The specimen contained a tumor with a stenotic lumen resembling a "lead pipe", an ulcerative portion, and mucosa with a granular appearance adjoining its proximal site. Many small aphthous lesions with IIa + IIc appearance were seen in the apparently normal mucosa. Histopathological examination confirmed a diagnosis of signet-ring cell carcinoma. The small aphthous lesions seemed to be metastases spread via the lymphatic vessels. Our review of the medical literature revealed three cases of signet-ring cell carcinoma of the jejunum; however, this is the first reported case of signet-ring cell carcinoma of the ileum. 相似文献
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We evaluated the prognostic value of immunostaining proliferating cell nuclear antigen (PCNA) by using a monoclonal antibody (PC10) in patients with parotid tumors. Twenty-seven cases were studied. Immunohistochemical studies were carried out on paraffin-embedded tissues from the patients, and the PCNA index was calculated as the percentage of positively staining tumor cells. The PCNA index ranged from 0.1 to 65.3%. We divided the 27 lesions into three groups histologically: group A with benign pleomorphic tumors (11 cases), group B with low-grade malignant tumors (5 cases), and group C with high-grade malignant tumors (11 cases). The mean PCNA index was 0.7% in group A, 2.0% in group B, and 23.1% in group C. The clinical data revealed a significantly higher local tumor recurrence and mortality rate in group C than in groups A and B. We conclude that PCNA may be used as an important indicator for determining clinical prognosis in parotid tumors. 相似文献
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A case of primary pure squamous cell carcinoma of the endometrium in a 50-year-old woman is reported. There was deep myometrial and para-cervical invasion. There is no evidence of metastases 2 years after total hysterectomy and salpingo-oophorectomy and radiation therapy. The patient is probably the youngest suffering from such a tumor. A detailed review of the literature has been carried out. 相似文献
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BACKGROUND: The occurrence of metastasis of renal cell carcinomas in the head and neck region is extremely rare. Metastasis in the larynx, hypopharynx, and the nasal sinuses has been reported. We report here about a 55-year-old female with metastasis in the soft palate and tonsil, which occurred 10 years following tumor nephrectomy. RESULTS AND CONCLUSIONS: The incidence of metastasis in renal cell carcinomas can be observed even many years following initial curative treatment of the primary tumor. Although rare in the region of the head and neck, they can often be mistaken for benign tumors such as hemangiomas or inflammatory tissue. The treatment of choice is radical surgical resection. 相似文献
11.
Pharyngeal lipoma with cartilaginous metaplasia (chondrolipoma): a case report and literature review
OG Nwaorgu EE Akang BM Ahmad FN Nwachokor AN Olu-Eddo 《Canadian Metallurgical Quarterly》1997,111(7):656-658
We report two cases of vasospastic angina associated with anaphylactic reaction caused by nonsteroidal anti-inflammatory drugs (NSAIDs). Both patients exhibited anaphylactic manifestations, such as general rash and urticaria, along with angina pectoris with electrocardiographic ST-segment elevations after suppository administration of diclofenac sodium or indomethacin, the most commonly used NSAIDs. Although these patients had normal coronary arteriograms, intracoronary administration of ergonovine or acetylcholine provoked diffuse coronary artery spasms accompanied by chest pain and ischemic ST-segment changes. It is therefore suggested that an allergic mechanism may be involved as a causative factor of the coronary artery spasm induced by NSAIDs. 相似文献
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A primary chondrosarcoma arising in the urinary bladder is described in a 73-year-old female, together with a review of the 2 previously reported cases in the literature. The clinical symptoms are similar to transitional cell carcinoma, but chondrosarcoma usually presents at an advanced stage, and the outcome is rather poor. This very rare and commonly poorly differentiated tumor should not be confused with poorly differentiated transitional cell carcinoma. The differential diagnosis from other lesions with chondroid features, such as chondroid metaplasia, osteosarcoma and carcinosarcoma, is discussed. The value of immunohistochemistry and electron microscopy in the differential diagnosis is demonstrated. 相似文献
13.
Y Abiko T Muramatsu Y Tanaka T Ohuchi M Satoh K Okumura T Shibata T Inoue M Kanazawa M Arisue M Shimono T Kaku 《Canadian Metallurgical Quarterly》1998,48(6):460-466
Clinicians can use data to improve daily clinical practice. This paper offers eight principles for using data to support improvement in busy clinical settings: 1) seek usefulness, not perfection, in the measurement; 2) use a balanced set of process, outcome, and cost measures; 3) keep measurement simple (think big, but start small); 4) use qualitative and quantitative data; 5) write down the operational definitions of measures; 6) measure small, representative samples; 7) build measurement into daily work; and 8) develop a measurement team. The following approaches to using data for improvement are recommended. First, begin with curiosity about outcomes or a need to improve results. Second, try to avoid knee-jerk, obstructive criticism of proposed measurements. Instead, propose solutions that are practical, goal-oriented, and good enough to start with. Third, gather baseline data on a small sample and check the findings. Fourth, try to change and improve the delivery process while gathering data. Fifth, plot results over time and analyze them by using a control chart or other graphical method. Sixth, refine your understanding of variation in processes and outcomes by dividing patients into clinically homogeneous subgroups (stratification) and analyzing the results separately for each subgroup. Finally, make further changes while measuring key outcomes over time. Measurement and improvement are intertwined; it is impossible to make improvements without measurement. Measuring and learning from each patient and using the information gleaned to test improvements can become part of daily medical practice in local settings. 相似文献
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Noma (Cancrum Oris/Ulcerogingivostomstitis) is a rare devastating grangrenous orofacial disease. It may lead to severe facial mutilation and deformities with dysfunctional effects. This disease primarily affects malnourished children from underdeveloped countries. It has recently been associated with AIDS in North America and Western Europe. We will be reporting and discussing the pathogenesis, bacteriological complications and treatments according to the literature. 相似文献
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Clinical reports have suggested an unusual frequency in the number of patients with food allergy to snails who are also allergic to the house-dust mite (HDM). As allergy to HDM is one of the most frequent sensitizations in atopic patients of Western countries, evaluation of the relevance of the concomitant sensitization to Dermatophagoides pteronyssinus and to snails is an important consideration. To evaluate the responsibility of different snail components and of snail mites for inducing in vivo hypersensitivity in patients allergic to HDM, the in vivo reactivity of patients with clinical symptoms after ingestion of snails was assessed by skin prick tests with extracts and hemolymph from four different Helix species snails, and extracts from the snail parasitic mite, Riccardoella limacum. In addition, to obtain epidemiologic data on cosensitization to HDM and snails in allergic patients, the frequency of snail sensitization and its relationship to HDM sensitization were determined in a population of 169 allergic children. All patients allergic to snails had positive skin prick tests to the snail extracts and none to R. limacum extract. The number of positive skin reactions did not significantly differ whatever the species, snail part, or heating procedure used. The strongest reactions were obtained with Helix pomatia (Burgundy snail). Among the 169 prospectively tested children, 38 had a positive prick test to snail extracts; 79% of the snail-sensitized children had sensitization to HDM; and 31% of the children allergic to HDM were found to be sensitized to snails. These results show that snail components, and not the mite R. limacum, were responsible for the in vivo hypersensitivity. These snail components reacting in vivo are present in different parts of snails, including the hemolymph. One-third of the children allergic to HDM were sensitized to snails without any previous ingestion of snails: this observation suggests that HDM was the sensitizing agent and that the cross-reaction could be clinically relevant in countries where eating snails is common. 相似文献
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For a period of 10 months, the perceptive-motor skills of golden hamsters were tested as part of an experiment to investigate vestibular controlled behaviour. We found that four out of 40 hamsters had more difficulties with swimming and equilibrium maintenance than the rest of the group. These disturbances either were apparent during the first months of testing or developed at a later period. In three hamsters the disturbances persisted over time while in one hamster performance in perceptive-motor skills increased. Histological examination with scanning electron microscopy revealed otoconial abnormalities in the saccule and/or the utricle. The otoconia were either malformed or replaced by spherulites. We conclude that the observed behavioural disturbances were caused by a defective peripheral vestibular organ. The results show similarities with data from pathology in other animals as well as in the human inner ear. 相似文献
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A case is reported of primary carcinoma of the ureteral stump with metastases following nephrectomy for benign disease. The occurrence of disseminated tumor at the time of diagnosis is uncommon, having been reported in only 3 previous cases. The autopsy findings are discussed and the literature is reviewed. 相似文献
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Primary angiosarcoma of the kidney is a rare tumor for which fewer than 10 case reports appear in the English literature. A case of primary renal angiosarcoma is reported, in which the tumor showed poorly differentiated spindled sarcoma admixed with typical angiomatous differentiation. Antibodies against CD31, CD34, Ulex europeus lectin type I, factor VIII-related antigen, cytokeratin (AE1/AE3), vimentin, S100 protein, epithelial membrane antigen, carcinoembryonic antigen, desmin, and smooth muscle actin were examined. CD31 showed strong diffuse membranous staining of cells in the well-differentiated areas and strong membranous staining in the spindled, poorly differentiated areas. CD34 showed strong cytoplasmic and membranous staining in both the poorly differentiated and well-differentiated areas. Staining for factor VIII-related antigen and Ulex europeus was less intense and was limited to the well-differentiated areas. Staining for cytokeratin (AE1-AE3), S100, carcinoembryonic antigen, epithelial membrane antigen, desmin, and smooth muscle actin were negative. Electron microscopy showed spindle cells containing abundant pinocytotic vesicles, vimentin-type intermediate filaments, and rare Weibel-Palade bodies. A complex karyotype was found. Our findings suggest that CD31 and CD34 are useful in defining endothelial differentiation in poorly differentiated angiosarcomas in which reactions for Ulex europeus lectin type I and factor VIII-related antigen may be equivocal. 相似文献